const { getLayout } = require('../../utils/layout');
// pages/discover/discover.js
const { api } = require('../../utils/request');
const { diaryEntry, albumEntry, memoryEntry } = require('../../utils/journal');
const { saveScrollPosition, getScrollPosition } = require('../../utils/scroll-pos');

Page({
  onResize: function() { this.setData(getLayout()); },
  data: {
    stats: null, loading: true, loadError: false, refreshing: false, publishOpen: false,
    activeFilter: 'diary', filters: [{value:'diary',label:'日记'}, {value:'album',label:'相册'}, {value:'memory',label:'记忆日'}],
    entries: [], albums: [], memories: [],
    scrollTop: 0
  },

  onLoad: function() {
    this.setData(getLayout());
    this.setData({ scrollTop: getScrollPosition('discover') });
  },
  onShow: function() {
    // 延迟设置 scrollTop，确保 scroll-view 在页面显示后重新应用滚动位置
    // 解决从子页面 navigateBack 返回后滚动位置丢失的问题
    var self = this;
    var savedTop = getScrollPosition('discover');
    this.setData({ scrollTop: savedTop });
    setTimeout(function() {
      self.setData({ scrollTop: savedTop });
    }, 100);
    this.loadStats();
  },

  // 保存滚动位置
  onScroll: function(e) {
    saveScrollPosition('discover', e.detail.scrollTop);
  },

  onPullDownRefresh: async function() {
    await this.loadStats(true);
    wx.stopPullDownRefresh();
  },

  loadStats: async function() {
    if (this._loading) return;
    this._loading = true;
    this.setData({loading:true, loadError:false});

    try {
      const [timeline, album, diary] = await Promise.all([
        api.timelineList(), api.albumList(), api.diaryList()
      ]);
      var photoCount = 0;
      if (Array.isArray(album)) {
        for (var i = 0; i < album.length; i++) {
          photoCount += parseInt(album[i].photo_count || 0);
        }
      }
      var stats = {
        timeline: Array.isArray(timeline) ? timeline.length : 0,
        album: photoCount,
        diary: (diary && diary.total) ? diary.total : 0,
      };
      this.setData({ stats: stats, entries: ((diary && diary.items) || []).map(diaryEntry), albums: (Array.isArray(album) ? album : []).map(albumEntry), memories: (Array.isArray(timeline) ? timeline : []).map(memoryEntry) });
    } catch (e) {
      console.error(e);
      this.setData({loadError:true});
    } finally { this._loading = false; this.setData({loading:false}); }
  },

  onRefresh: async function() { this.setData({refreshing:true}); try { await this.loadStats(); } finally { this.setData({refreshing:false}); } },
  selectFilter: function(e) { this.setData({activeFilter:e.currentTarget.dataset.filter}); },
  showPublish: function() { this.setData({publishOpen:true}); },
  hidePublish: function() { this.setData({publishOpen:false}); },
  noop: function() {}, preventMove: function() {},
  _publish: function(type) { this.hidePublish(); this._savePosBeforeLeave(); wx.navigateTo({url:'/pages/publish/publish?type=' + type}); },
  writeDiary: function() { this._publish('diary'); },
  uploadPhotos: function() { this.hidePublish(); this._savePosBeforeLeave(); wx.navigateTo({url:'/pages/albums/albums?upload=1'}); },
  createAlbum: function() { this._publish('album'); },
  createMemory: function() { this._publish('timeline'); },
  openJournalEntry: function(e) { this._savePosBeforeLeave(); wx.navigateTo({url:'/pages/diary_detail/diary_detail?id=' + e.currentTarget.dataset.id}); },
  openAlbum: function(e) { this._savePosBeforeLeave(); wx.navigateTo({url:'/pages/album/album?album_id=' + e.currentTarget.dataset.id}); },
  // 跳转前保存当前滚动位置
  _savePosBeforeLeave: function() {
    saveScrollPosition('discover', this.data.scrollTop);
  },

  // Tab 导航（替换，不留栈）
  goHome: function() { this._savePosBeforeLeave(); wx.redirectTo({ url: '/pages/index/index' }); },
  goToDiaryFromDiscover: function() { this._savePosBeforeLeave(); wx.navigateTo({ url: '/pages/diary/diary?from=discover' }); },
  goToProfile: function() { this._savePosBeforeLeave(); wx.redirectTo({ url: '/pages/profile/profile' }); },

  // 功能入口（推入栈，支持左滑返回）
  goToTimeline: function() { this._savePosBeforeLeave(); wx.navigateTo({ url: '/pages/timeline/timeline' }); },
  goToAlbum: function() { this._savePosBeforeLeave(); wx.navigateTo({ url: '/pages/albums/albums' }); },
  goToSongs: function() { this._savePosBeforeLeave(); wx.navigateTo({ url: '/pages/lovewords/lovewords' }); },
  goToCheckin: function() { this._savePosBeforeLeave(); wx.navigateTo({ url: '/pages/punch/punch' }); },
  goToPet: function() { this._savePosBeforeLeave(); wx.navigateTo({ url: '/pages/pet/pet' }); },
  goToPeriod: function() {
    this.hidePublish();
    this._savePosBeforeLeave();
    wx.navigateTo({ url: '/pages/period/period' });
  }
});